While on the Create a Post page, if you have only a Facebook account selected OR only a Twitter account selected OR only a LinkedIn account selected, you can tag/mention a user by typing @ and then some letters:
If you have more than 1 social network account selected, you will need to click the ✏️ icon to customize your post for each social network:
Once you select the Facebook, Twitter, or LinkedIn tab, you will then be able to tag/mention users in your post:
Instagram's API does not have a username suggestion feature like Facebook, Twitter, and LinkedIn do, but you can tag/mention users in Instagram posts by simply putting their @username in the caption of your post
NOTE: You can only tag company pages on LinkedIn. Tagging of personal LinkedIn profiles is not supported by LinkedIn's API.
Updated on: 10 / 03 / 2022